1. Technical Field
The present disclosure relates to a spectrometry device, an image forming apparatus, and a spectrometry method.
2. Related Art
In the related art, a wavelength-selective interference filter may be capable of switching a transmitted wavelength by changing the dimension of a gap between reflecting films and a colorimetry device including the wavelength-selective interference filter. See, for example, JP-A-2013-238755.
In the colorimetry device of JP-A-2013-238755, a measurement target is irradiated with light, and light reflected by the measurement target is incident on the wavelength-selective interference filter. Light of a predetermined wavelength is transmitted by the wavelength-selective interference filter and is detected by a detector. At this time, the dimension of the gap between the reflecting films is sequentially changed by controlling the wavelength-selective interference filter to sequentially switch the wavelength of transmitted light, and the intensity of light of each wavelength is detected by the detector. Accordingly, a spectrum of the measurement target can be measured (color is measured).
Colorimetry may be performed on a color patch while the colorimetry device disclosed in JP-A-2013-238755 is moved in one direction at, for example, a constant speed. In such a case, the intensity of light is required to be obtained in a plurality of wavelengths desired to be measured while a measurement target region is moved by the colorimetry device in the color patch.
However, a change in the speed of movement of the colorimetry device, a shift in the position of installation of the color patch, or the like may cause the measurement target region to pass beyond the color patch during the period of time from the start of measurement until the end of measurement or cause the measurement to be started at an excessively early timing. Thus, the position of an area of measurement of the color patch may be shifted. In such a case, since colorimetry is performed at a position deviated from the color patch, colorimetry cannot be accurately performed on the color patch, and colorimetry accuracy is degraded.